Open-end spinning apparatus

ABSTRACT

Into the rotary spinning chamber of an openend spinning apparatus there is, for cleaning purposes, periodically introduced a jet of pressurized air directed to the circumferential fiber collecting groove provided in the wall of the spinning chamber. The pressurized air, together with the impurities dislodged thereby, is withdrawn from the spinning chamber through an air outlet means having an annular inlet opening which is situated adjacent the fiber groove and which surrounds the rotary axis thereof.

United States Patent [191 Grau [ 1 OPEN-END SPINNING APPARATUS [75] Inventor: Gerhard Grau,Ebersbach, Germany [73] Assignee: Zinser-Textilmaschinen GmbH,

Ebersbach, Germany [22] Filed: Nov. 30, 1972 [21] Appl. No.: 310,793

[30] Foreign Application Priority Data Nov. 30, 1971 Germany 2159248 [52] US. Cl. 57/56, 57/58.89 [51] Int. Cl DOlh 1/12 [58] Field of Search.. 57/58.89-58.95, 56

[56] References Cited UNITED STATES PATENTS 7/1969 Storek et a1. 57/58.89

[ 1 Mar. 12, 1974 Landwehrkamp et a1. 57/56 3,557,542 l/197l Oskin et al 57/58.89 3,584,452 6/1971 Schiltknecht et a1. 57/58i89 3,698,175 10/1972 Dykast 57/58.89 3,739,565 6/1973 Nagel 57/58.89

Primary Examiner-John Petrakes Attorney, Agent, or Firm-Edwin E. Greigg [57] ABSTRACT Into the rotary spinning chamber of an openend spinning apparatus there is, for cleaning purposes, periodically introduced a jet of pressurized air directed to the circumferential fiber collecting groove provided in the wall of the spinning chamber. The pressurized air, together with the impurities dislodged thereby, is withdrawn from the spinning chamber through an air outlet means having an annular inlet opening which is situated adjacent the fiber groove and which surrounds the rotary axis thereof.

10 Claims, 1 Drawing Figure 1 OPEN-END SPINNING APPARATUS BACKGROUND OF THE INVENTION This invention relates to an open-end spinning apparatus having a spinning rotor which is provided at its internal wall with a fiber collecting groove (hereinafter referred to as fiber groove). The spinning rotor is disposed in a housing chamber and has an open radial face into which there extends a stationary yarn guiding body containing a yarn outlet channel. The apparatus is further of the type that is provided with a blow nozzle which is connected to a pneumatic source and which serves for blowing pressurized air in the direction of the fiber groove for the purpose of cleaning the same.

In open-end spinning apparatus, for the purpose of spinning the fibers into the open-ended yarn, it is necessary to cause an air stream to travel in the yarn'outlet channel in a direction opposed to the normal advancing direction of the yarn. This air stream then flows into the inner chamber (spinning chamber) of the spinning rotor. The penumatic transportation of the opened individual fibers into the spinning chamber also causes a continuous inflow of the air thereinto.

In a known open-end spinning apparatus of the aforenoted type, such as disclosed in Swiss Pat. No. 466,768, in which the fiber groove is cleaned periodically by pressurized air, the withdrawal of air flowing into the rotor chamber and the withdrawal of pressurized air blown into thefiber groove during the cleaning operation are effected through the hollow rotor shaft, that is, through a central air outlet channel in the rotor. The inlet opening of this central air channel which is relatively small and which is of circular configuration, is disposed exactly opposite the yarn outlet channel, that is, in exact alignment therewith. This arrangement has, among others, the disadvantage that the impuritiesdislodged from the fiber groove by means of the pressurized air have to be conveyed towards the central inlet opening of the air outlet channel against the centrifugal force generated by the rotation of the spinning rotor. Consequently, in case of relatively high rotor rpms, the removal of the impurities from the spinning chamber is not reliably ensured. Further, the long flow paths of the pressurized air from the fiber groove to the central air outlet channel is in principle disadvantageous regarding the removal of the dislodged impurities from the inner chamber of the rotor, since the flow speed of the pressurized air drops substantially along its path to the air outlet channel and generates in the spinning chamber uncontrollable eddy currents which tend to substantially hinder the removal of the dislodged impurities. Further, to guide the air in the manner taught by the prior art is also disadvantageous regarding the spinning of the yarn, since for this purpose the yarn has to be carried in the spinning chamber from the yarn outlet channel to the fiber groove. Thus, there prevails the danger that this yarn does not reach the fiber groove, but is sucked out through the aforedescribed central air outlet channel.

OBJECT, SUMMARY AND ADVANTAGES OF THE INVENTION aforediscussed disadvantages are no longer present.

Briefly stated, according to the invention, the spinning rotor in the zone of its inner wall which adjoins that side of the fiber groove that is remote from the open end of the spinning rotor, has an annular inlet opening which forms part of an air outlet means and which surrounds the geometrical rotary axis of the fiber groove. Through this annular inlet openingair including the pressurized air blown into the rotor cham ber for cleaning may flow out of the spinning chamber.

By means of the aforeoutlined measure the pressurized air blown into the spinning chamber during the cleaning of the fiber groove is admitted rapidly and securely into the air outlet. In this manner the impurities dislodged by the pressurized air remain in the pressurized air stream and arrive securely and completely to the air outlet means through which they are removed from the spinning chamber. Due to the short-length flow path of the pressurized air in'the inner chamber of the rotor, fewer uncontrollable turbulent streams are generated therein. Consequently, higher speeds of the pressurized air stream may be used and accordingly, more thorough and more rapid cleaning of the fiber groove may be effected.

The invention will be better understood as well as further objects and advantages become more apparent from the ensuing detailed specification of a preferred, although exemplary embodiment of the invention taken in conjunction with the sole figure illustrating the preferred embodiment in longitudinal axial section.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the FIGURE there is illustrated a housing 1 1 which defines a chamber 10 forming part of an open-end spinning apparatus, details of which that are not pertinent to the invention are not illustrated for the sake of clarity. The chamber 10 accommodates a spinning rotor 9.

It is noted that an open-end spinning machine contains a great plurality of spinning apparatuses such as illustrated inthe FIGURE and now to be described.

The chamber 10 is closed by means of a cover 12 which may be opened, for example, by tilting it about hinges, not shown. At its side oriented towards the chamber 10, the lid 12 has a rotationally symmetrical projection which constitutes a yarn guiding body 13 extending into the inner chamber (spinning chamber) 16 of the spinning rotor 9 through the open radial face thereof. The yarn guiding body 13 contains a throughgoing central yarn outlet channel 14 through which the spun yarn is continuously taken out and thus removed from the housing 11. The cover IZ-and the yarn guiding body 13 contain, in a conventional manner, a fiber supply channel 15 through which the individual fibers are introduced into the spinning chamber 16 by virtue of an air stream.

The annular clearance between the inner face of the cover 12 and the annular radial edge face bounding the open side of the spinning rotor 9 is so small that practically no air may flow therethrough.

The cover 12 further has a bore 17 which passes through the yarn guiding body 13 spaced from the yarn outlet channel 14 and which terminates in a blow nozzle 19 opening into the spinning chamber 16. The bore 17 is, in a manner not shown, connected by means of a pressure conduit to a pressurized air source (also not In general, it is sufficient to apply the pressurized air jet only after relatively long intervals (for example, every 23 days). Or, it is also expedient to effect this air blast while the spinning rotor 9 is slowing down from its operational speed to standstill. For this purpose there may be provided means which turn on the air jet for a predetermined period automatically when driving of the spinning rotor 9 is interrupted. Or, the cleaning of the fiber groove 20 may be automatically effected when yarn breakage occurs. This is a logical time to clean, since often the yarn breakage is caused by an excessive soiling of the fiber groove. Open-end spinning apparatuses are often provided with means which, upon the occurrence of yarn breakage, auto-- matically carry the yarn backwards from the yarn outlet channel to the fiber groove for restarting the spinning. These means include a sensor which is responsive to the slackening of the yarn tension and which emits a signal for restarting the spinning. This signal may then be additionally used to initiate a short-period flow of pressurized air through the blow nozzle 19 onto the fiber groove 20. If the cleaning is effected upon yarn breakage, it is expedient to automatically brake the rotor, so that the cleaning operation is effected at lower than normal rotor rpms.

The geometrical longitudinal axis of the blow nozzle 19 is inclined to the geometrical axis of the rotor 9 and is oriented towards the fiber groove 20. The outlet opening of the blow nozzle 19 is at a distance from the radial plane defined by the base of the fiber groove 20 and is disposed at that side of the aforenoted plane which is oriented towards the open end 21 of the spinning rotor 9. At the other side of the aforedescribed radial plane there is disposed, at a small distance therefrom (preferably 1 3 mm), the inlet opening 22 of an air outlet means 23 of the rotor 9. The plane of the annular inlet opening 22 is indicated with a dash-dot line. The inlet opening 22 may be rotationally symmetrical, but it is also feasible to provide a rotationally nonsymmetrical configuration therefor. Thus, the inner bounding edge of the air inlet opening 22 may have a wave-shaped course. The air flowing into the spinning chamber 16 may be withdrawn therefrom through the air outlet means 23 and introduced into the housing chamber 10. From the latter, the air may be taken out through one ormore air outlet channels connected in a known manner to one or more vacuum sources. Or, the air may be drawn from the chamber by an air drain generated by the rotation of the rotor 9, provided that this suction effect is sufficient to generate the required flow rate. The air that is admitted to the spinning chamber 16 through the fiber supply channel and the yarn outlet channel 14 and the pressurized air admitted to the spinning chamber 16 for the cleaning of the fiber groove are both withdrawn through the air outlet means 23.

In the preferred embodiment the air outlet means 23 is constituted by a clearance between two spaced components 24 and 25 forming the spinning rotor 9. The rotationally symmetrical, generally ring-shaped component 24 forms 'a circumferential wall which contains the fiber groove 20. The rotationally symmetrical, generally disc-shaped component 25 of the rotor 9 forms a radial wall portion which is held at-a distance'from the component by spacers 26 which are traversed by bolts 27 securing the components 24 and 25 firmly to one another. In a central bore of the rotor component 25 there is inserted a solid rotor shaft 28 which is supported in the housing 11 in a manner not shown and is driven externally of the housing 11 by means (also not shown) such as a tangential drive belt assembly.

The inlet opening 22 of the outlet means 23 begins very close to the fiber groove 20 (for example, at a distance of approximately 2 mm) and has the configuration of an annulus, the plane of which is normal to the rotary axis of the rotor 9. The arrangement of the inlet opening 22 in the immediate vicinity of the fiber groove 20 is particularly advantageous in case of yarn breakage, since the aforediscussed backward transportation of the yarn from the yarn outlet channel to the fiber groove 20 is not hindered by the pressurized air jet. This is so because the pressurized air leaves the spinning chamber 16 immediately from the fiber groove 20 and is thus not admitted to the vicinity of the yarn outlet channel 14.

The rotor component 25 has a frustoconical elevation 29 which is rotationally symmetrical with respect to the rotary axis of the rotor 9 and the radial face of which is disposed at a small distance (for example, 4 5 mm) from the yarn guiding body 13. This clearance provides for the yarn which is formed during the spinning, a passage from the fiber groove 20 to the yarn outlet channel 14.

The fiber groove 20 is joined in the direction of the air outlet means 23 by a convex, rotationally symmetrical wall portion 30 of the rotor component 24. The wall portion 30 is shaped in such a manner that the inner diameter of the rotor component 24 continuously decreases from the base of fiber groove 20 until a location which is situated 1 2 mm within the air outlet 23 across the inlet opening 22. Thus, the wall face 30 has an approximately funnel-shaped, rotationally symmetrical configuration. This design of the zone 30 is particularly advantageous to obtain an effective, rapid air flow that leaves the remainder of the spinning chamber 16 unaffected. By virtue of the frustoconical projection 29 which is disposed radially inwardly spaced from the zone 30, there is obtained at a short partial zone 31 of the air outlet means 23 a funnel-like cross section that adjoins the inlet opening 22. This short zone 31 of the air outlet 23 extends practically parallel to the geometrical rotary axis of the rotor 9. The zone 31 continues in a zone 32 of the outlet channel 23. The zone 32 extends radially outwardly to the outer circumference of the spinning rotor 9 and is divided into several outlet portions by the spacers 26 in the zone thereof. For example, five spacers 26 may be provided which reduce the total cross section of the air outlet 23 only in an insubstantial manner in their zone. 5

By virtue of the abovedescribed design of the air outlet means 23, the outlet opening 35 of the air outlet means 23 is at a greater radial distance from the rotor axis than the outer edge of the inlet opening 22, so that the impurities which are blown into the air outlet means 23 during the cleaning of the fiber groove 20 are rapidly and securely transported into the chamber surrounding the rotor 9 with the aid of centrifugal forces imparted thereon.

To enhance the withdrawal of air from the spinning chamber 16, the air outlet means 23 may be provided with impeller vanes (not shown). Or, in the rotor wall bores (also not shown) may be provided which are inclined to the rotor axis and which form channels for the air outlet means 23.

The impurities are removed from the chamber 10 where they can no longer have an adverse effect on the spinning operation through outlets (not shown) extending from the chamber 10. The outlet opening 35 has the surface of a relatively large-diameter, relatively small-height circular cylinder.

As it may be observed in the drawing, the pressurized air is guided by means of the design of the inlet opening 22 and the zone 30 in such a manner that immediately downstream of the fiber groove it enters the air outlet 23 and the dislodged impurities are blown directly into the air outlet 23.

The design of the rotor 9 according to the invention substantially enhances the cleaning of the fiber groove, the removal of the dislodged impurities and the withdrawal of pressurized air. Also, during the normal spinning operation and for the initial spinning of fibers into the yarn it provides particularly advantageous air flow conditions in the spinning chamber 16.

What is claimed is:

1. In an open-end spinning apparatus of the known type that has (a) a housing chamber, (b) a spinning rotor disposed in said housing chamber and having internal wall means and an open radial face, (c) a spinning chamber defined by said internal wall means of said spinning rotor, (d) a fiber groove provided in said internal wall means and having a base, said fiber groove dividing said wall means into a first wall portion extending between said fiber groove and said open radial face and a second wall portion separated from said open radial face by said fiber groove, (e) a stationary yarn guiding body projecting through said open radial face of said spinning rotor, (f) a yarn outlet channel provided in said stationary yarn guiding body, said yarn outlet channel communicating with said spinning chamber, (g) a blow nozzle having an opening in said spinning chamber, said blow nozzle being oriented toward said fiber groove for periodically emitting a pressurized air jet theretoward for cleaning the same, the improvement comprising air outlet means for guiding air out of said spinning chamber, said air outlet means including an inlet opening provided in said second wall portion of said internal wall means, said inlet opening having an annular configuration and spacedly surrounding the geometrical rotary axis of said spinning rotor.

2. An improvement as defined in claim 1, wherein said inlet opening begins immediately adjacent said fiber groove.

3. An improvement as defined in claim 1, including a rotationally symmetrical surface forming part of said second wall portion, said rotationally symmetrical surface extending from the base of said fiber groove into said air outlet means, said rotationally symmetrical surface having a funnel-shaped configuration between said base and at least said inlet opening, said rotationally symmetrical surface having its greatest diameter at said base.

4. An improvement as defined in claim 1, said air outlet means including a rotationally symmetrical zone extending from said inlet opening approximately parallel to said geometrical rotary axis of said spinning rotor.

5. An improvement as defined in claim 1, said inlet opening having an outer bounding edge, said air outlet means having an outlet opening, the distance of said outlet opening from said geometrical rotary axis of said spinning rotor being greater than the distance of said outer bounding edge from said geometrical rotary axis of said spinning rotor.

6. An improvement as defined in claim 5, wherein said outlet opening is provided on the outer circumference of said spinning rotor.

7. An improvement as defined in claim 1, said inlet opening having a rotationally symmetrical configuration.

8. An improvement as defined in claim 1, wherein the width of said air outlet means continuously decreases along a predetermined length from said inlet opening.

9. An improvement as defined in claim 8, including a frusto-conical wall portion bounding air outlet means along said predetermined length.

10. An improvement as defined in claim 1, said spinning rotor comprising A. a first component containing said fiber groove, B. a second component having a radial face constituting a radial base wall of said spinning chamber, C. means securing said first and second components to one another to form a rigid unit, and D. spacer means disposed between said first and second components to maintain a clearance therebetween, said clearance constituting said air outlet means. 

1. In an open-end spinning apparatus of the known type that has (a) a housing chamber, (b) a spinning rotor disposed in said housing chamber and having internal wall means and an open radial face, (c) a spinning chamber defined by said internal wall means of said spinning rotor, (d) a fiber groove provided in said internal wall means and having a base, said fiber groove dividing said wall means into a first wall portion extending between said fiber groove and said open radial face and a second wall portion separated from said open radial face by said fiber groove, (e) a stationary yarn guiding body projecting through said open radial face of said spinning rotor, (f) a yarn outlet channel provided in said stationary yarn guiding body, said yarn outlet channel communicating with said spinning chamber, (g) a blow nozzle having an opening in said spinning chamber, said blow nozzle being oriented toward said fiber groove for periodically emitting a pressurized air jet theretoward for cleaning the same, the improvement comprising air outlet means for guiding air out of said spinning chamber, said air outlet means including an inlet opening provided in said second wall portion of said internal wall means, said inlet opening having an annular configuration and spacedly surrounding the geometrical rotary axis of said spinning rotor.
 2. An improvement as defined in claim 1, wherein said inlet opening begins immediately adjacent said fiber groove.
 3. An improvement as defined in claim 1, including a rotationally symmetrical surface forming part of said second wall portion, said rotationally symmetrical surface extending from the base of said fiber groove into said air outlet means, said rotationally symmetrical surface having a funnel-shaped configuration between said base and at least said inlet opening, said rotationally symmetrical surface having its greatest diameter at said base.
 4. An improvement as defined in claim 1, said air outlet means including a rotationally symmetrical zone extending from said inlet opening approximately parallel to said geometrical rotary axis of said spinning rotor.
 5. An improvement as defined in claim 1, said inlet opening having an outer bounding edge, said air outlet means having an outlet opening, the distance of said outlet opening from said geometrical rotary axis of said spinning rotor being greater than the distance of said outer bounding edge from said geometrical rotary axis of said spinning rotor.
 6. An improvement as defined in claim 5, wherein said outlet opening is provided on the outer circumference of said spinning rotor.
 7. An improvement as defined in claim 1, said inlet opening having a rotationally symmetrical configuration.
 8. An improvement as defined in claim 1, wherein the width of said air outlet means continuously decreases along a predetermined length from said inlet opening.
 9. An improvement as defined in claim 8, including a frusto-conical wall portion bounding air outlet means along said predetermined length.
 10. An improvement as defined in claim 1, said spinning rotor comprising A. a first component containing said fiber groove, B. a second component having a radial face constituting a radial base wall of said spinning chamber, C. means securing said first and second components to one another to form a rigid unit, and D. spacer means disposed between said first and second components to maintain a clearance therebetween, said clearance constituting said air outlet means. 